The present invention relates to a conduit plate adapter suitable for use in an open-end spinning device.
Conduit plate adapters are known, for example in German Patent Publication DE 43 34 485 A1. Such conduit plate adapters comprise preferably a circular base body with a conically designed contact surface on its back side and having a mouth that extends into a spinning rotor during spinning operations. The mouth of the conduit plate adapters has dimensions that are adapted to a certain spinning-rotor diameter or to a diameter range. A mouth of a yarn guide conduit is inserted into the mouth of the conduit plate adapter. A centrally arranged yarn withdrawal nozzle is also present.
Previously known conduit plate adapters further comprise a central passage bore into which a yarn withdrawal nozzle is fixed in a replaceable manner at an entrance side and into which a yarn withdrawal tube engages on an exit side opposite the entrance side.
The yarn withdrawal nozzle replaceably fixed in the central passage bore typically comprises of a special holding body and a ceramic nozzle mouth fastened in a non-detachable manner to the holding body, as disclosed in German Patent Publication DE 195 44 617 A1. The holding body, which is generally ferromagnetic, engages permanent magnet inserts that are disposed in the conduit plate adapter, thus fixing the holding body in the conduit plate adapter in a non-positive manner.
These conduit plate adapters, which are well known, have proven themselves in practice and make it possible to create optimal spinning conditions in open-end spinning devices. For example, if the spinning rotors are replaced by smaller spinning rotors during a batch change, then the conduit plate adapters can also be replaced in a relatively simple manner by conduit plate adapters with an adapted mouth. Moreover, in such a batch change, the spinning material can also be taken into consideration by appropriately selecting the yarn withdrawal nozzle, that is arranged in a readily replaceable manner in the conduit plate adapter. Further, the spinning of the yarn can be influenced via the imparting of a false twist.
However, these previously known conduit plate adapters have the disadvantage that they are quite expensive to manufacture and use. In addition, it can occur in exceptional instances, especially in the case of difficult yarns, that the magnetic attachment of the yarn withdrawal nozzle fails to hold sufficiently and the yarn withdrawal nozzle rotates in its receiving central passage bore, which has a negative effect on the yarn being produced.
The present invention attempts to overcome the disadvantages of the previously cited state of the art by creating a conduit plate adapter that is economical to manufacture and is also reliable to operate.